On Sat, Oct 02, 2004 at 02:07:43PM -0700, Barton Bosch wrote:

I have some 1200 dpi scans that need to be scaled down, sharpened with unsharp mask and then saved as jpgs at ~50% quality setting.

i am curious for the reason for saving at the 50% quality setting. fiddling with the quality setting is good to do if you are trying to improve the load speed of a web page and perhaps to save disc space if this is a problem.

i guess i would like to know what the purpose is for the image.

Should the operations be performed in the order above or would it be better to scale->save as 50% qual jpg->unsharp mask->save as 100% qual jpg?

saving should be only one step and the last step. the unsharp mask should be the second to the last step. if sharpening is necessary, it should be done on each size that you save. so in short:

1) scale 2) sharpen
3) save

carol

On Sat, Oct 02, 2004 at 09:11:25PM -0700, Barton Bosch wrote:

Yup, just trying to make the document a little lighter weight. The basic purpse of the doc is as a series of reference charts and tables that will be hyperlinked -- eliminating the need to repeatedly refer to the paper book that the scans were taken from.

Nothing especially exciting, but I am learning about different practices for high quality image manipulation in The GIMP.

you might consider using indexed png's for this. jpgs are definately best for photographs but indexed pngs are very light weight and do not look that bad. to index an image Image -->Mode -->Indexed. this reduces the colors from billions of colors to 256 colors and is a very good way to handle many simpler images.

carol